A young couple walked free from court on Friday after being cleared of killing their four-month-old son who was suffering from rickets.

Rohan Wray, 22, and Chana Al-Alas, 19, of the Barnsbury Estate, Islington, fell under suspicion when their baby Jayden died two years ago. But, following a six-week trial at the Old Bailey, charges of murder and causing or allowing his death were dropped.

Jayden died from brain damage and swelling which caused a number of seizures, but nearly 60 medical, professional and expert witnesses were unable to agree the cause.

The prosecution originally claimed the brain damage could only have been caused by shaking or his head being hit against something.

But Mr Wray and Ms Al-Alas denied causing any injury to Jayden and their defence maintained that the fractures and seizures were linked to rickets owing to a Vitamin D deficiency in his mother which was only discovered after his death.

Barristers for the couple argued that they had been loving parents and had not put a foot wrong with Jayden’s care but had been “pre-judged” by doctors and police.

Prior to his emergency hospital admission in July 2009, they had taken him to see doctors and to hospital when worried about his health but medical staff and health visitors had not detected anything wrong with him.

Judge Stephen Kramer said it was unsafe to let the case go before the jury because no-one had been able to agree if the injuries were caused by trauma or medical complications, and directed the jurors to return not guilty verdicts.

The couple, who were 16 and 19 when Jayden was born, hugged and kissed when they learned that their ordeal was over.

The case comes amid legal warnings to prosecutors that shaken baby cases should be supported by other evidence of abuse.

Jenny Wiltshire, Ms Al-Alas’s solicitor, said outside court: “Chana Al-Alas and Rohan Wray can now be allowed to grieve the tragic loss of their son who they loved and cherished.

“They have been through two and a half years of hell. They were prevented from comforting their dying son or attending his christening – all because clinicians at both hospitals failed to diagnose congenital rickets.”

She added: “The real criminality in this case is that, if the money spent on this case had been directed to fulfilling the 1991 Government directive that breastfeeding mothers be given vitamin D supplements, this death would not have occurred and rickets, which is now back up to epidemic proportions in this country, would have been wiped out.”